The Infrared Properties and Period-Luminosity Relations of Red Supergiant Stars in the Magellanic Clouds

Transcription

1 The Infrared Properties and Period-Luminosity Relations of Red Supergiant Stars in the Magellanic Clouds Ming Yang Biwei Jiang Jan / 16 / 2013

2 Outlines Introduction Sample Selection and Data Analysis Period-Luminosity Relation Pulsation mode

3 Outlines Introduction Sample Selection and Data Analysis Period-Luminosity Relation Pulsation mode

4 Introduction Red Supergiant stars (RSGs) are massive evolved, He-burning, extreme Population I stars with mass range roughly between 9-30 M. Relative cool effective temperatures about K (belonging to spectral type late-k M) Enormous radii which could up to 1500R High luminosities that about L Large mass loss rate (MLR): some RSGs stars could reach 10 6 to 10 4 M yr 1.

5 Introduction Red Supergiant stars (RSGs) are massive evolved, He-burning, extreme Population I stars with mass range roughly between 9-30 M. Relative cool effective temperatures about K (belonging to spectral type late-k M) Enormous radii which could up to 1500R High luminosities that about L Large mass loss rate (MLR): Some RSGs stars could reach 10 6 to 10 4 M yr 1.

6 RSGs have long been known for their hundreds days of semi-regular photometric variation (belong to SRc in General Catalogue of Variable Stars (GCVS) ) It may due to the radial pulsation at fundamental, first or even possibly second overtone mode The inexplicable long term scale variability which could up to 4000 days or more so called Long Secondary Period (LSP) The source of LSP still not quite sure.

7 The irregular photometric variation (belong to Lc in GCVS) It may caused by the large convective cells in the surface of the star and some recent simulation works have proofed it

8 The period-luminosity (P-L) relation Cepheid P-L relation There still does need a variety of independent methods which could be used to verified. RSGs P-L relation

9 Outlines Introduction Sample Selection and Data Analysis Period-Luminosity Relation Pulsation mode

10 Contamination Sample selection Foreground red dwarf ~ B-V vs. V-R (B band is sensitive to the surface gravity) Red giants in the halo of the Milky Way ~ kinematic analysis AGBs

11 LMC Total: 191 candidates Feast et al ~ 21 Pierce et al ~ 10 Kastner et al ~ 25 Massey et al ~ 135 SMC Total :140 candidates Catchpole et al ~ 20 Wood et al ~ 6 Massey et al ~ 101 Levesque et al ~ 8 Massey et al ~ 1 van Loon et al ~ 3 van Loon et al ~ 1

12 Infrared data (1 search radius): SAGE IRAC Catalog SAGE MIPS 24um Catalog Photometry data: All Sky Automated Survey (ASAS) MAssive Compact Halo Objects (MACHO) projects

13 Spatial distribution Data analysis

14 Color-Magnitude Diagrams K S vs. J K S * background from Bonanos et al. (2009, 2010); m bol =-7.1 (Wood et al. 1983)

15 Color-Magnitude Diagrams K S vs. J K S * background from Bonanos et al. (2009, 2010); m bol =-7.1 (Wood et al. 1983); J Ks cuts are from Cioni et al. (2006a, 2006b) (Boyer et al. 2011)

16 Color-Color Diagrams [3.6] [8.0] vs. [8.0] [24]

17 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

18 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

19 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

20 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

21 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

22 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data

23 Given all these characteristics in color and brightness, the situation is complicate Low luminosity and no much dust to account for the low luminosity [3.6] [8.0] vs. [8.0] [24] Lack bands data Targets are confirmed as RSGs LMC: 185 SMC: 132

24 Photometric data Light curve morphology The definition of RSGs variables is semi-regular with amplitudes of about 1 mag

25 Period Determination Phase Dispersion Minimization (PDM) PDM2: improved curve fits, suppressed subharmonics, and beta function statistics

26 Period04 (Fourier analysis) Top panel is the 10 day-binned light curve with the fitted curve Bottom panels are power spectra

27 CLEAN From top to bottom: The dirty spectrum clean components residual spectrum clean spectrum

28 Weighted Wavelet Z- transform (WWZ) From top to bottom: The contour map The time-varying amplitude The time-varying period

29 LMC SMC

30 Outlines Introduction Sample Selection and Data Analysis Period-Luminosity Relation Pulsation mode

31 K S -band P-L relation 47 targets 21 targets

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33 Compare with the P-L relations of RSGs derived by other jobs

34 Multi-band Infrared P-L relation Near- and Mid-infrared P-L relations of RSGs in SMC and LMC

35 Multi-band Infrared P-L relation Near- and Mid-infrared P-L relations of RSGs in SMC and LMC

36 Multi-band Infrared P-L relation Near- and Mid-infrared P-L relations of RSGs in SMC and LMC

37 * LPV in MCs from Soszynski et al. (2007); Superposed AGB a2 sequence

38 Outlines Introduction Sample Selection and Data Analysis Period-Luminosity Relation Pulsation mode

39 Pulsation Mode Comparison with Guo & Li (2002)

40 Comparison with Guo & Li (2002)

41 Comparison with Heger et al. (1997)

42 Publications 1. The Period-Luminosity Relation of Red Supergiant Stars in the Small Magellanic Cloud, Yang, M., Jiang, B. W., 2012, ApJ, accepted 2. Analysis of a Selected Sample of RR Lyrae Stars in LMC from OGLE III, Chen, B. Q., Jiang, B. W., Yang, M., 2012, RAA, submitted 3. Construction of the Database for Pulsating Variable Stars, Chen, B. Q., Yang, M., Jiang, B. W., 2012, ChA&A, 36, 脉动变星数据库的建立, 陈丙秋, 杨明, 姜碧沩, 2011, 天文学报, 52, Red Supergiant Stars in the Large Magellanic Cloud. I. The Period- Luminosity Relation, Yang, M., Jiang, B. W., 2011, ApJ, 727, The Variability Of RSG : HV2576, Yang, M., Jiang, B. W., 2008, IAUS, 252, 267

43 END THANKS